Turn the microwave on its back so that the door of the microwave is facing the ceiling. Peel a rubber bumper off its backing and stick it onto the bottom of the microwave -- use one bumper for each corner. In addition to giving the microwave height so that air can circulate underneath it, the bumpers will also make it level on your countertop.
Allow the adhesive on the bumpers to fully cure according to the manufacturer's instructions on the package. This usually takes around two hours. Allowing the adhesive to set ensures that they don't slide around once you turn the microwave right-side up.
Set the microwave right-side up, and turn it around so that the back is facing you. Connect the appliance cord into the wire sticking out of the microwave by plugging the lose wire into the cord. The cord will allow you to plug your microwave into an outlet instead of still being wired over your stove. Use the zip ties to bundle the cord so that it is not hanging all over your countertop.
Make sure that the microwave is not sitting flush against the wall -- air needs to circulate around the back of it, and you don't want the cord to be forced against the wall either. Plug in your microwave